The overall aim of this study is to use an experimental design to investigate the effect of an adherence-enhancing 16-week aerobic exercise training protocol on resting blood pressure and mood in women, ages 18-60, with unmedicated mild hypertension. The overall aim of the second part of this study is to utilize an experimental design, in the initial exercise group, to study the effect of long-term exercise training, effectiveness of CDC/PACE counseling, and factors which predict long-term adherence.